RGBCube/serenity
1
Fork 0
mirror of https://github.com/RGBCube/serenity synced 2025-05-31 06:48:12 +00:00
Code Issues Activity Actions

LibJS: Update AST to use completions :^)

Browse source 
This is another major milestone on our journey towards removing global
VM exception state :^)
Does pretty much exactly what it says on the tin: updating
ASTNode::execute() to return a Completion instead of a plain value. This
will *also* allow us to eventually remove the non-standard unwinding
mechanism and purely rely on the various completion types.
This commit is contained in:
Linus Groh 2022-01-02 21:37:50 +01:00
parent 95acb1ce88
commit da856d7742
11 changed files with 507 additions and 692 deletions
Download patch file Download diff file Expand all files Collapse all files

23
Userland/Libraries/LibJS/Runtime/ECMAScriptFunctionObject.cpp
View file

@ -431,9 +431,7 @@ ThrowCompletionOr<void> ECMAScriptFunctionObject::function_declaration_instantia
} else if (parameter.default_value) {
// FIXME: Support default arguments in the bytecode world!
if (interpreter)
argument_value = parameter.default_value->execute(*interpreter, global_object());
if (auto* exception = vm.exception())
return throw_completion(exception->value());
argument_value = TRY(parameter.default_value->execute(*interpreter, global_object())).release_value();
} else {
argument_value = js_undefined();
}
@ -715,27 +713,26 @@ void ECMAScriptFunctionObject::async_block_start(PromiseCapability const& promis
// c. Remove asyncContext from the execution context stack and restore the execution context that is at the top of the execution context stack as the running execution context.
vm.pop_execution_context();
// NOTE: Running the AST node should eventually return a completion.
// Until it does, we assume "return" and include the undefined fallback from the call site.
// NOTE: Eventually we'll distinguish between normal and return completion.
// For now, we assume "return" and include the undefined fallback from the call site.
// d. If result.[[Type]] is normal, then
if (false) {
// i. Perform ! Call(promiseCapability.[[Resolve]], undefined, « undefined »).
MUST(call(global_object, promise_capability.resolve, js_undefined(), js_undefined()));
}
// e. Else if result.[[Type]] is return, then
else if (!vm.exception()) {
else if (result.type() == Completion::Type::Return || result.type() == Completion::Type::Normal) {
// i. Perform ! Call(promiseCapability.[[Resolve]], undefined, « result.[[Value]] »).
MUST(call(global_object, promise_capability.resolve, js_undefined(), result.value_or(js_undefined())));
MUST(call(global_object, promise_capability.resolve, js_undefined(), result.value().value_or(js_undefined())));
}
// f. Else,
else {
// i. Assert: result.[[Type]] is throw.
// ii. Perform ! Call(promiseCapability.[[Reject]], undefined, « result.[[Value]] »).
auto reason = vm.exception()->value();
vm.clear_exception();
vm.stop_unwind();
MUST(call(global_object, promise_capability.reject, js_undefined(), reason));
MUST(call(global_object, promise_capability.reject, js_undefined(), *result.value()));
}
// g. Return.
return js_undefined();
@ -823,11 +820,9 @@ Completion ECMAScriptFunctionObject::ordinary_call_evaluate_body()
if (m_kind == FunctionKind::Regular) {
TRY(function_declaration_instantiation(ast_interpreter));
auto result = m_ecmascript_code->execute(*ast_interpreter, global_object());
if (auto* exception = vm.exception())
return throw_completion(exception->value());
// NOTE: Running the AST node should eventually return a completion.
// Until it does, we assume "return" and include the undefined fallback from the call site.
auto result = TRY(m_ecmascript_code->execute(*ast_interpreter, global_object()));
// NOTE: Once 'return' completions are being used, we can just return the completion from execute() directly.
// For now, we assume "return" and include the undefined fallback from the call site.
return { Completion::Type::Return, result.value_or(js_undefined()), {} };
} else if (m_kind == FunctionKind::Async) {
// 1. Let promiseCapability be ! NewPromiseCapability(%Promise%).